Spark plug



Oct. 27, 1925. ,5 8 3 I I J. W. RIDOLF SPARK-PLUG Filed Dec. 15, 1925 Patented 0a. 27, 1925.-

Joann; w. amour, or savan'nm, enonom.

' SPARK PLUG.

Applleatlonflled December 15, 18 83. Serial llo. 880,864.

To wh'omiit may concern Be it known that I, J OSEPH W. RIDOLF, a

citizen of the United States, residin" at Savannah, in the county of Chatham, State of Georgia, have invented certain new and useful Improvements in Spark Plugs, of

' which the following is a description, referonce being had to the accom anying drawing, and to the figures of re erence marked thereon.

The invention relates to new and uwful improvements in spark plugs for internal combustion engines.

An object of the invention is to provide a spark plug which is formed with a substantially enclosed firing chamber for housing the points of the electrodes.

A further object of the. invention is to provide a spark plug of the above type with relatively small ports leading to the firing chamber, through which the gas in the cylinder is admitted to the firing chamber, said ports operating to exclude a large portion of the oils carried in suspension in the gas.

A further object:of-- the invention is to provide a spark plug of the above type wherein the ports are so positioned and ar-' rangedas to direct the gas on its initial entrance into the firing chamber against a porcelain member of the'plug and away from the points of the spark electrodes.

These and other objects will in part'be obvious and will in part be hereinafter more fully disclosed. a

In the drawings which show by way' of illustration one embodiment of the invention Figure 1 is a longitudinal sectional view. through the spark plug embodying my improvements, and.

Fig. 2 is a sectional view on the line 22 of Fig. 1.

Fig. 3 is a side elevation of the bottom section of the spark plug, showing the extsrnal arrangement otthe communicating s 0t.

Fig. 4 is a section corresponding to Fig. 1, on an enlarged scale, showing the currents of gas in the iower portion of the spark plug chamber.

It is well known that/in the operation of an internal combustion engine there is'much oil carried in suspension in the gas, and this oil collects on the points of the electrodes of portion of the plug.

the spark plug, ca-rbonizes, and in a short time, accumulates to such an extent as to produce a short circuit and foul the plug.

The invention is directed broadly to a construction of plug which will exclude to a large extent t \e oils carried in suspension in the gas. This is accom lished by providing a substantially (IlClOSGt firing chamber for the spark electrodes and admitting the gas to this chamber through relatively small ports. These small ports are preferably made in the side walls of the chamber instead of the end wall, and serve to separate the ieavy ()llS in suspension 111 the gases and keep hem from entering into the firing chamber. Some sum-ll portion, however, will pass through with the gas, and I have therefore, shaped and located the ports 50 that the inrushing gas strikes against the porcelain of the plug well above the points of the electrodes. The oil in suspension will cling to the porcelain through adhesion, and therefore. the gas is further freed from what little oil is left in suspension therein. The gas, after striking the porcelain, circulates about and finally comes downaround the spark points, and when'it reaches the spark points, it is substantially free from oil so that when ignited there will be no carbon deposit on the points foul the plug.

Referring more in detail to the drawings, I have shown the invention applied to the usual form of plug which consists of a body portion 1 having a porcelain center portion 2 through which extends the electrode 3.

Said porcelain portion is secured to the body portion by means of a sleeve nut 4: which bears against a gasket 5. The porcelain portion also seats on a gasket 6 so that it makes gastight connection with the body Said body portion of the plug has a downwardly projecting sleeve 7 formed with a thread 8. This sleeve is closed at its upper end by means of the porcelain which is provided with a cone-shaped part 9 extending down into the chamber of the sleeve. I have closed the lower end of this sleeve by means of a cap or end member 10. In order to accomplish this, I have bored out the body portlon as indicated at 11, so as to receive a reduced. portion 12 formed on the cap 10. This is preferably of the electrodes, and consequentlv no ac cumulating of carbon deposits which will constructed so as to make a tight fit when inserted in the bored out portion of the sleeve 7. by a solid section, and centrally thereofis a threaded opening which receives the other electrode 13. Said electrode is preferably formed with a slot to receive a screw driyer so that it may be screwed in or out to adjust the distance between the points 14 and 15 of the spark electrodes. This cap closesnthe lower end of the chamber in the sleeve 7 and forms a substantially enclosed firing chamber in. which is located the spark electrodes. Said cap or end member is provided with slots 16, 17 and 18. These slots are similar 'in construction. Each slot inclines up- Wardly as shown in the drawings, at an angle of about sixty degrees to a plane transversely of the plug. The slots are relatively narrow. When the gas in the cylinder is put under compression, it will pass through these ports 16, 17 and 18 into the firing chamber of the plug, said ports being formed in the side walls of the plugsand inclined, will practically exclude all the oil carried in suspension in the gas. The gas passing through the ports on its initial entrance to the firing chamber, will be directed upwardly away from the points of the electrodes and against the cone-shaped portion 9 of the porcelain member, as indicated by the arrows in the drawings.

It is well known that when the gas strikes this porcelain member, the remaining oil in suspension will to quite a large extent, adhere to the wall. of the porcelain, and thus further aids in the freeing of the gas of all' heavy oils in suspension. The gas passes u along the side wall of the porcelain an circulates back down into the chamber of the sleeve and finally encloses the points of the electrodes. When .the gas, however, reaches the points of the electrodes, it has been'practically freed of all oil in suspension, and is a dry, highly atomized gas. When the spark-takes place, the gas, "of

course, will be ignited, and during the combustion of the gas, the oil clinging to the wall of the porcelain will be burned ofi. On

"the seavaging stroke of" the piston, theburned gases left in the firing chamber of the spark plug will be expelled, leaving more or less ofa vacuii'min the chamber which aids in the bringing in of the fresh gas for the next ignitionperiod. -This vacuum in ,l the fi -ring chamber of the spark plug not only' faids inbringing in the gas, but in the bringing of. the dry gas freed from the oils This cap has its lower end formed to a position about the points of the electrodes.

' Vhile I have described the slots as formed in the side walls of the end cap, it will be' spark plug as closed by a cap or end member, it will be understood, oicourse, that this end member may be integral with the body portion of the spark plug and not in the form of a detachable cap. It is also understood that the end member or cap may be otherwise secured to the body portion than by the method described above. Then again, it will be understood that this plug may be made in different sizes, and appliedtointernal gas engines for any use.

It 1s obviousthat -m1nor changes 1n the details of construction and arrangement of the parts may be made without departing from the spirit of the invention as set forth in the appended claim.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is-

A sparkplug comprising a body portion having a firing chamber, the end of said body portion being closed, a porcelain member carried by said body portion and extending into said firing chamber, a spark electrode extending through said porcelain member and cooperating with a spark electrode located centrally of said closed end, the sidewalls of said body portion having a plurality of inclined ports, said ports being relatively small so as to exclude from the firing chamber a large portion of the 011s carried in suspension in the gas, and said ports being inclined relative to the side wall of said body portion so as to direct the gas on its initial entrance into the firing chamber against the porcelain member and away from the points of the spark electrodes whereby any oil carried by the gas in suspension into the 3 firing chamber will be caused to adhere to the porcelain member and separated from the gas.

In testimony whereof, I afiix my signature.

- JOSEPH W. 'RIDOLF. 

